Magnetic heater



Dec. .19, 1961 A. M ARTHUR MAGNETIC HEATER Filed June 20, 1960 aazazaza f0 INVENTOR. 4nvde 444a4e7v/Me F|G.5 BY

477'OE VE Y United States Patent Ofifice 3,014,116 Patented Dec. 19, 1961 3,014,116 MAGNETIC HEATER Arthur MacArthur, 14 Whitehall Road, East Brunswick, NJ. Filed June 20, 1960, Ser. No. 37,374 7 Claims. (Cl. 219-42) This invention relates to a heater which may be installed in automobiles or adjacent to any source of mechanical energy. The invention has particular reference to a current generator which generates eddy currents within a rotating disk, these currents being immediately transformed into heat and the heat thus generated blown to a desired space.

Many types of heaters for small confined spaces such as the interior of automobiles have been designed and used. 7

Many of the heaters have used resistance coil set in front of a fan. These heaters are expensive to operate because they use so much electrical energy which must be supplied by the automobile generating system. Other types of heaters use the heat generated by exhaust gases as they pass through an exhaust manifold. Such installations provide heated air only when the engine has been running for some time and therefore they sulfer a time lag of about ten minutes. Where automobile heaters employ water from the engine cooling system the heaters are both slow and expensive. The present invention generates heat immediately and uses only mechanical power which may be furnished by an automobile power plant or some other source of rotary power. One of the arrangements to be described uses electromagnets as components of the system and these, of course, draw some current from the generating system. However, this current drain is quite small and the current furnished to the electromagnets is a very small fraction of the current necessary as compared to that needed, to supply resistors when they are used exclusively for heating purposes.

One of the objects of the present invention is to provide an improved heater which avoids one or more of the disadvantages and limitations of prior art arrangements.

Another object of the present invention is to convert rotary mechanical energy into heat at high efiiciency.

An object of the present invention is to provide a heaterblower combination having few parts and arranged for quick assembly and repair.

A further object of the present invention is to vary the heat generated by a control device which can be adjusted over a Wide range of heat generating values.

Another object of the present invention is to provide a unitary rotor disk which is both a fan and a heater.

A further object of the present invention is to provide a heater having no high unit surface temperatures such as might cause explosions or burns.

The invention comprises a rotor disk of nonmagnetic electrically conductive material driven by a source of mechanical power. Magnetic means are provided for generating magnetic flux in a core which directs lines of magnetic force through portions of the rotor disk and thereby generates large eddy currents. A plurality of fan blades are formed integral with the rotary disk for producing air currents adjoining the disk surfaces and directing the heater air toward a desired space.

The invention consists of the construction, combination and arrangement of parts, as herein illustrated, described and claimed.

In the accompanying drawings, forming a part hereof are illustrated several forms of embodiment of the invention, in which drawings similar reference characters designate corresponding parts, and in which:

FIGURE 1 is a plan View of one form of heater made in accordance with the present invention.

FIGURE 2 is a side view of the heater shown in FIG- URE l with certain parts broken away to show its construction.

FIGURE 3 is a cross-sectional view of a portion of a fan blade and is taken along line 3-3 of FIGURE 1.

FIGURE 4 is a cross-sectional view of one of the elec' tromagnetic coils, with parts broken away to show the internal construction of the coil member, taken along line 4-4 of FIGURE 1.

FIGURE 5 is a side view of a portion of a heater showing an alternate arrangement which uses a permanent magnet for producing magnetic lines of force.

FIGURE 6 is a view similar to FIGURE 2 showing the use of a plurality of fan disks in a heater, another embodiment of the present invention.

Referring to the drawings and particularly FIGURES l- 4, the heater includes a base member 10, which is preferably made of some soft iron and is formed with two bent end portions 11. Midway between the two ends, a rotor shaft 19 is mounted within bearings 12 and 13 secured to base member 10 for journaling the shaft and maintaining the rotary components in a definite plane. One end of the shaft is secured to a pulley 14' which is coupled to any convenient part of a source of rotary power. Other forms of coupling may be used. At the other end of the shaft 19, a rotor disk 15, formed of a suitable non-magnetic and electrically conductive material such as copper, aluminum or silver, is secured by means of washers 16 and a nut 17. The rotor 15 is formed with a flat peripheral portion and an intermediate area containing fan vanes 18. Vanes 18 are punched from portions of the rotor disk 15 and this method of formation not only produces a unitary blade of the same material as the disk, but also provides cutout spaces 20 for the passage of air.

Near the turned up portion 11 of the iron member 10, are mounted two or more electromagnets 21. These magnets include a core of soft iron 22 which is securely joined to base member 10. The electromagnet also include a winding 23, the ends of which are to be connected to a source of direct current power (not shown). The upper portion of core 22 is provided with a pole piece 24 and this pole piece cooperates with a return path member 25 positioned in parallel relationship and forming with the pole piece 24 an air gap which is occupied by the peripheral portion of the rotor disk 15. The upper return path member 25 may be secured directly to the turned up portion 11 of the base 10 but for purposes of adjustment, the return path member 25 is hinged as indicated at 33 to the end of the bent portion 11 and contains an extended lever arm 26 which may be controlled by a Bowden wire 27. Cooperating with the lever arm 26 is a limit stop 28 and a spring 30. It is to be understood that the air gap between the pole piece 24 and return path member 25 may also be fixed at a desired spacing.

The operation of this device is as follows: Direct current applied to winding 23 produces a strong magnetic field having lines of force which pass between the pole piece 24 and return path member 25, and in so doing pass through the periphery of rotor 15. The return path of the flux is through the hinge on return path member 25 and through the end portion 11 to the base member 10 and the core 22. Mechanical power is applied to pulley 14 which turns the shaft 17 and rotor 15 at a high rate of speed and in so doing generates currents within the rotor disk, these currents being at once transformed into heat. The rotor disk 15 is preferably made of copper or aluminum and the heat generated in the periphery travels to the vanes 18 which blow the air through the disk and heat it during its passage adjacent to the vane surfaces.

The amount of magnetic flux generated by the electromagnets 21 is proportional to the length of the air gap between pole pieces 24 and return path members 25. Changing the length of this gap varies the amount of magnetic flux passing through the rotor and thereby varies the amount of heat generated in the rotor disk. The air gap may be varied in a number of ways, the mechanism shown in FIGURES 1 and 2 being shown as an example. In the position shown in FIGURE 2 the movable pole pieces 25 are at the position which produces the shortest gap and therefore generates the most heat. Pulling on wires 27 moves the control levers 26 away from stops 28 to increase the air gap length and reduce the amount of heat generated. If this heater is installed in a car the wires 27 may be joined to a control knob on the dash board for easy and convenient adjustment of heat generated.

In addition to varying the air gap the output of the device may be varied by changing the voltage supplied to the coils 23.

The alternate arrangement shown in FIGURE is the same as the described arrangement except that permanent magnets 31 are secured to the ends of base member 10. These permanent magnets produce magnetic lines of force which travel across an air gap to return path members 25. The operation is the same as described above.

In the embodiment shown in FIGURE 6, a plurality of rotors are mounted upon the shaft 19 in spaced relationship. The ends of the rotor disks 15 pass between a series of spaced segments 34 which may be made of soft iron or Alnico. Alternately, the segments 34 may be made of Alnico and soft iron arranged that so every other segment is formed of the same material. The segments 34 are secured to a soft iron bar 35 which forms the return path for the magnetic flux. End segment members 36, 37, are provided in the structure and one or both of said segments 36, 37, is of magnetic material such as an Alnico magnet.

The segment 37 is hinged as indicated at 38 for the purpose of varying the gap 39 between the end segment 37 and the next adjacent segment 34. In this manner the amount of heat produced by the assembly may be varied at will. Control means such as have been hereinabove described in connection with FIGURE 2 may be connected to the end segment 37 to produce the variation in gap size. The rotor 15 is provided with blades 18 in the manner previously set forth and as the shaft 19 is rotated by a suitable source of power, heat will be generated and air driven through the vane will pick up the heat and direct it into the area which is to be warmed. The magnetic path through this embodiment is through the rim of the copper rotor disks because of the iron segments 34 which are disposed adjacent thereto.

Having thus fully described the invention what is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A heater comprising; a rotor disk of non-magnetic electrically conductive material driven by a source of rotary power, a core system forming a complete ferromagnetic path except for an air-gap between two pole pieces having parallel faces, a base which rotatably supports said disk and to which is secured said core so that the periphery of the disk is positioned in the air-gap, electric means for generating magnetic flux in the core system, and a plurality of fan blades formed integral with said rotor disk and positioned external to the airgap, said blades arranged for producing air currents passing through the disk to direct heat away from the disk.

2. A heater as set forth in claim 1 wherein said means for generating magnetic flux includes a winding around a portion of said core system for connection to a source of direct current power.

3. A heater as set forth in claim 1 wherein said rotor is made of copper.

4. A heater as set forth in claim 1 wherein said rotor is made of aluminum.

5. A heater as set forth in claim 1 wherein said rotor is made of silver.

6. A heater comprising; a rotor disk of non-magnetic electrically conductive material, a shaft secured to the center of said disk, a bearing means for rotatably supporting the shaft and disk, a core system forming a complete ferromagnetic path except for an air-gap between two pole pieces having parallel faces, a base member to which is secured the bearing means and the core system so that the periphery of the disk is positioned in the airgap, electric means for generating flux in the core system, and a plurality of fan blades formed integral with said rotor disk and positioned external to the air-gap, said blades arranged for producing air currents passing through the disk to direct heat away from the disk.

7. A heater comprising; a rotor disk of non-magnetic electrically conductive material driven by a source of rotary power, a core system forming a complete ferromagnetic path except for an air-gap between two pole pieces having fiat faces, a portion of said core system including one of said pole pieces secured to a hinge and coupled to an adjustable means for moving said pole piece to vary the length of said air-gap, a base which rotatably supports said disk and to which is secured said core system so that the periphery of the disk is positioned in the airgap, electric means for generating magnetic flux in the core system, and a plurality of fan blades formed integral with said rotor disk and positioned external to the air-gap, said blades arranged for producing air currents passing through the disk to direct heat away from the disk.

References Cited in the file of this patent UNITED STATES PATENTS 2,088,604 Littlefield Aug. 3, 1937 2,549,362 Bessiere et al. Apr. 17, 1951 2,566,274 White et a1. Aug. 28, 1951 

